Method and apparatus for sequentially forming sheet metal with spaced dies



Nov. 18, 1958 J. MCDONALD 2,850,635

METHOD AND APPARATUS FOR SEQUENTIALL! FORMING SHEET METAL WITH SPACEDDIES Filed May 14, 1956 2 Sheets-Sheet 1 m m i 7 N k F 7 m m T n F \41 or I W INVENTO JOHN MCDONALD BY W".,

Nov. 18, 1958 MCDONALD 2,860,685

METHOD AND APPA us FOR SEQUENTIALLY FORMING SHEET METAL WITH SPACED DIESFiled May 14, 1956 2 Sheets-Sheet 2 JZ H-Z F/ /5 g INVENTOR.

JOHN M DONALD United States Patent METHOD AND APPARATUS FOR SEQUENTIALLYFORMING SHEET METAL WITH SPACED DIES John McDonald, Westlake, Ohio,assiguor of one-half to Bruce B. Krost, Cleveland, Ohio Application May14, 1956, Serial No. 584,708

13 Claims. (Cl. 153-21) My invention relates to apparatus and method forforming sheet metal into desired cross-sectional conformation. 1

An object of my invention is to press a strip of sheet metal ofrelatively flat or simple form to a desired crosssectional form.

Another object is the provision for modifying the cross-sectional formof a strip of sheet metal without the use of rollers usually used toroll sheet metal into desired cross-sectional conformation.

Another object is the provision of apparatus and method for formingcomplex cross-sectional forms in a strip of sheet metal with an economyof apparatus and manufacturing steps utilized.

Another object is the provision for forming a strip of sheet metal intoforms not readily obtainable with the use of mating rolls.

Another object is the provision of apparatus and method for pressingsheet metal into desired cross-sectional conformation and having blindarches or construction not readily obtainable by the use of priorapparatus and methods.

Another object is the provision for forming metal by a series of spacedmating die members so arranged and constructed as to provide desiredresults in the form of the sheet metal with a maximum of economy andefliciency. r

Another object is the provision of apparatus and method for producingresults not heretofore obtainable.

Other objects and a fuller understanding of my invention may be had byreferring to the following description and claims taken in conjunctionwith the accompanying drawings, in which:

Figure 1 is a longitudinal elevational view of apparatus embodying myinvention;

Figure 2 is an enlarged plan view of a length of sheet metal strip goingthrough its various stages of forming from its simple fiat form to itsdesired conformation of more complex nature;

Figure 3 is a cross-sectional view of the strip of sheet metal takenthrough the line 3-3 of Figure 2;

Figure 4 is a cross-sectional view of the strip of sheet metal takenthrough the line 4-4 of Figure 2;

Figure 5 is a cross-sectional view of the strip of sheet metal takenthrough the line 5-5 of Figure 2;

Figure 6 is a cross-sectional view of the strip of sheet Figure 8 is across-sectional view of the strip of sheet metal taken through the line8-8:of Figure 2;

Figure 9 is a cross-sectional view of the strip of sheet I l metal takenthrough the line 9-9 of Figure 2;

Figure 10 is a cross-sectional view of the strip of sheet metal takenthrough the line 10-10 of Figure2; Figure 11 is an enlarged fragmentaryview of one of the pairs of mating die members in the apparatus shown rin Figure 1 and illustrates the front face of the last pair of matingdie members in the sequence located adjacent the right-hand end of theapparatus shown in Figure 1;

Figure 12 is an enlarged cross-sectional view of the pair of mating diemembers shown in Figure 11 and taken through the line 12-12 of Figurell;

Figure 13 is an enlarged sectional view taken through the line 13-13 ofFigure 11;

(In Figures 12 and 13 for purposes of clarity of illustration the stripof sheet metal is not shown between the mating die members.)

Figure 14 illustrates a modified form of mating die members when afloating mandrel is utilized in the forming of the strip of sheet metal;and

Figure 15 is another modified form of mating die members in which blindarches or open spaces are formed in the strip of sheet metal Without theutilization of a floating mandrel.

My apparatus is carried on a rigid frame denoted generally by thereference character 21. The frame 21 has upright standards or legs 22and a bed plate or bottom supporting beam 23 carried by the legs 22.Positioned above and spaced from the bedplate 23 is a longitudinal beam24. The beam 24 and bedplate 23 are substantially parallel to each otherand extend longitudinally of the frame 21. A shaft 25 journaled on theframe 21 is driven by a belt 28 which drivingly engages a pulley 27 onthe shaft 25 and a driving pulley 29 which, in turn, is driven by anelectric motor 30 supported on the frame 21. Thus, the motor 30 throughthe pulleys 29 and 27 and connecting belt 28 rotates the shaft 25.

Adjacent the opposite ends of the shaft 25 where it is journaled to theframe 21, there are eccentric bearing mechanisms 26 which are sointerconnected with the 1 shaft 25 and beam 24 as to reciprocate thebeam 24 in a vertical direction, that is, upwardly and downwardly,relative to the frame 21 as the shaft 25 is rotated. asmuch as theeccentric bearing mechanisms 26 are of the usual form for translatingrotary motion into reciprocating motion, and commonly utilized inreciprocating die mechanisms, the detailed construction of the eccentricbearing mechanisms 26 has not been illustrated.

There are a plurality of mating die members A, B, C,

die member of each pair of die members.

The lower and stationary die members of the respective pairs of diemembers have been indicated by the reference characters A-2, B2, C2,D-2, E-2, F-2 and G-2. These stationary die members are rigidlysupported in position and carried by the bedplate 23 by means ofsuitable brackets connecting the bedplate 23 with the of die membershave been indicated by the reference characters A-l, B-l, C-l, D-l, E-1,F-l and G-1.

These upper die members are rigidly carried by means of suitablebrackets to the reciprocating beam 24, so

that as the beam 24 moves up and down, the upper die The mating diemembers are spaced 34 passes through a guide member 41 which slidablyreceives the strip 35' and guides it in a longitudinaldirection so as topass between the several pairs of die members.

A feed mechanism 31 iscarried by the beam "24 and ispo'sitioned' betweenpairs of di'emembers A and B inamanner to' engage the strip 35. Thefeedmechanism is adapted to advance the strip 35 in increments, uponeach reciprocal movement of-the'beam 24; in a'manner to advance-thestrip 35"toward the'r ight in'the apparatus in intermittentand-successive stages; In other words, the feed mechanism 31 advancesthe strip--35 through the apparatus step-by-step in accordance with thereciprocatingmovement of the upper die memberscarried by the beam 24.

Adjacent the right-hand end of the apparatus, there is acut-off device32 which is actuated by a limit'switch so as to cut off a predeterminedlengths of the strip after it has been completely formed bythe series ofpairs of die members and as -it--leaves the last pair of die members G.A cut-off blade carried by the reciprocating upper die member 64 isadapted to cut off the strip on the rearward side of the die members Gupon actuation of the cut-01f device 32 when the protruding stripencouters the limit switch of the cutoff device 32. By adjusting thecut-off device 32, pieces of the strip in the desired cross-sectionalconformation and of the preselected length are cut off after beingformed. These cut off lengths of. the. formed strip then drop down intoa suitable receptacle.

The opposed mating. die. members have opposed surfaces which aredirected toward each other in a manner to. engage the strip 35 as itpasses between the opposed die members. The opposed surface of the upperdie member is identified by the reference character 42 and the opposedsurface of the lower die member is identified by thereference character43. In the case of all of the die-members of the series of die members,the opposed surfaces 42 and 43 are parallel to each other and are normalto the plane in which the opposed die members are disposed. and 43 ofthe several pairs of die members and which engage and press therebetweenthe strip 35 are at right angles to the plane of the reciprocatingmovement of the upper die members. All components of force resultingfrom the reciprocation of the upper die members relative to thelower diemembers and the strip engaging the opposed surfaces 42 and 43 aremaintained within the plane of the reciprocating movement. In otherwords, there is no component of force between the opposed die memberswhich tends to thrust one of the die members forwardly or rearwardlyrelative to the otherdie members. The disposition of the opposedsurfaces 42 and 43 assist in maintaining all components of forcewithinthe plane of opposed die members, this plane. being disposedtransversely of the apparatus.

Each of the pairs of die members in the series hasa different contour orshape on the opposed surfaces'42 and 43 of the respective pairs of diemembers. The contour of die members A is relatively simple and forms buta slight bend in the strip 35. Each of the succeeding pairsof diemembers, reading from left to right in Figure 1, provides an additionalbend or change in the form of the strip. These changes in form progressfrom the initial and simple fiat form of the strip as it enters theapparatus to a desired cross-sectional conformation as it leaves theapparatus. In the particular embodiment illustrated, the contour or formof the opposed surfaces 42 and 43 of the plurality of mating die membersA to G, inclusive, are best illustrated by viewing the crosssectionalconformation of the strip 35 at the location of each of the pairs of diemembers. The form of strip within the apparatus and showing theprogressive changes in its form is illustrated in Figure 2. Thecross-sectional conformation of the strip at various locations In otherwords, the opposed surfaces. 42

along the course of the strip through the apparatus is seen in Figures 3to 10, inclusive. the strip 35 in its substantially flat form and asseen looking in the direction of the arrows 33 of Figure 2.

At the location of the opposed die members A, where the first forming isdone, the strip is bent to have the conformation indicated by thereference character 35a and is illustrated in Figure 4.

' At the location of opposed die members B and between theopposedsurfaces therof, the strip 35 assumes the shape indicated by thereference character 35b and is illustrated in Figure 5.

At the location of the die members C and between the opposed. surfacesthereof, the strip has a cross-sectional conformation indicated by thereference character 35c and is illustrated in Figure 6.

At the location of the opposed die members D, the strip acquires thecross-sectional conformation indicated by'th'e reference character 35dand is illustrated in Figure 7.

At the location of the opposed die members E, the strip acquires theconformation indicated by the reference character 35e and is illustratedin Figure 8.

At the location of the .opposed die members F, the strip acquires thecross-sectional conformation indicated by the reference character 35fand is illustrated in Figure 9.

At the location of the opposed die members G, the strip acquires theconformation indicated by the reference character 35g' and isillustrated by the Figure 10.

Theshapes or contours of the opposed surfaces 42' and 43 of-therespective pairs of die members complement the shapes of the stripillustrated in Figures 4 to 10, inclusive. Inotherwords, the shapes orcontours of the pairs of diemembers are arranged in a sequence whichInasmuch as the preceding form of the strip is different from the spacebetween opposed surfaces42 and 43 of each following pair of die members,it is apparent that the strip as it approaches each of the pairs of diemembers is .out of phase with the shape or contour of the particularpair of die members that it is approaching. To accommodate the diemembers so as to readily receive. the strip in its precedingconformation and at the same time to maintain the desired disposition ofthe 0pposed surfaces 42 and 43, there are provided camming guidesurfaces 36 and 37 upon the several pairs of die members. The cammingguide surface on the upper and movable die members is denoted by thereference character. 36. The camming guide surface on the lower orstationary die members is indicated by the reference character 37. Theguide surfaces are adapted to gradually funnel and bend the strip 35from its preceding conformation so as to readily enter the space betweenthe opposed surfaces 42 and 43 of each pair of die members.

It is seen that the strip 35 in 'its flat form as it approaches thefirst die members .A does .not fully complement the shape or contour ofthe opposed surfaces 42 and 43- althoughasindicated it is preferable tohave all of the- Figure 3 illustrates pairs of die members soconstructed as to provide this described camming and guiding function.As noted in Figures 12 and 13, the camming guide surfaces 36 and 37extend in a parabolic curve forwardly from the opposed surfaces 42 and43, respectively, toward the forward face of the die members which isdirected toward the preceding pair of die members; that is, toward theside from which the strip approaches the pair of die members. In somearrangements, the camming guide surface may be omitted from one of thedie members of each pair of die members. For example, in the making of aV-shaped longitudinal member from a flat strip, the lower die memberonly may have the camming guide surface provided on it as this diemember meets the strip in its preceding flatter form. Because not asnecessary in such a situation, the camming guide surface could beeliminated or be more limited in extent on the upper die member.However, usually it is desirable to have the camming guide surfacesprovided on both the die members of each pair of die members.

In Figure 11, the shape or contour of the opposed die members G1 and 6-2is illustrated. As seen, this shape or conformation of the opposedsurfaces 42 and 43 of die members G-1 and G-2 is arranged to provide theconformation 35g to the strip, that is, the form illustrated in Figure10.

The feed mechanism 31 is so constructed and arranged as to feed thestrip 35 forwardly through the apparatus in successive increments. Thesesuccessive increments are in general governed by the effective length ofthe opposed surfaces 42 and 43 which press and form the sheet metaltherebetween. By having the metal fed in increments which aresubstantially equal to or less than.

the effective length of the opposed surfaces 42 and 43 of the respectivepairs of die members, it is assured that the whole length of the strip35 is eventually and successively pressed and formed by opposed surfaces42 and 43 of each of the several pairs of die members. The step-by-stepfeeding of the strip in desired increments is obtained by the adjustmentof the feed mechanism 31 which advances the strip 35 in thepredetermined increment upon each stroke of the reciprocating beam 24and upper die members carried thereby.

Of course, various modified constructions can be utilized in theadaptation of my apparatus and method for forming strip into differentdesired cross-sectional conformations. One of the modifications of theapparatus and one of the several ways in which the invention may beutilized is illustrated in Figure 14. In Figure 14, the lower die memberis denoted by the reference character H-2 and the reciprocating diemember is denoted by the reference character H-ll. A strip in theconformation indicated by the reference character 3542 has blind archesor open spaces therein usually not accessible by opposed die members.One of the ways to form a strip in the conformation 35-h is by utilizinga floating mandrel 38, which is held in alignment by a suitable socketin the upper die member H-ll. This mandrel 38 floats freely with thestrip so as to be maintained within the partially closed pocket formedby the bending of the strip into the conformation 35-11. As the stripleaves the apparatus, it extends beyond the mandrel 38 and at the sametime additional strip is fed to a position between the die members H-1and H-2 and to be formed around the floating mandrel 38.

Another modification in the use of the invention is illustrated inFigure 15. Here the lower die member is indicated by the referencecharacter J2 and the upper or reciprocating die member is indicated bythe reference character JIl. In this modification, the upper die memberJl has a tongue portion 39 which protrudes downwardly between the throator open space provided between the in-turned sides of the strip in theconformation indicated by the reference character 35 The tongue 39 movesdownwardly to form the bottom corner of the through the open top of thestrip in the conformation 35-j. This arrangement leaves the blind archesor open.

spaces 40 within the strip of conformation 35-j on each lateral side ofthe tongue 39. This illustrates another manner of forming the strip intodesired. conformation, including conformations having blind or otherwiseinaccessible interior portions.

The apparatus and method also lends itself readily to other variationsand adaptations for the forming of sheet metal strip into desiredconformation. It is readily seen that strip sheet metal may beefficiently and economically formed without the need of expensive matingrollers and without a large massive die. The same apparatus may beutilized for forming a strip of fiat sheet metal into other desiredconformations by merely substituting other pairs of die members for thepairs of die members A to G, inclusive. The die mmebers are easily andcheaply made and may be produced in a much shorter period of time thanis necessary for the fabrication of mating rollers and for thefabrication of massive and complex dies.

The invention is particularly useful when a relatively short run is tobe made in forming strip sheet metal into desired cross-sectionalconformation.

The present disclosure includes that contained in the appended claims,as well as that of the foregoing description.

Although this invention has been described in its pre ferred form andpreferred practice with a certain degree of particularity, it isunderstood that the present disclosure of the preferred form andpreferred practice has been made only by way of example and thatnumerous changes in. the details of construction and the combina tionand arrangement of parts and steps may be resorted to Without departingfrom the spirit and scope of the invention as hereinafter claimed.

What is claimed is:

1. Apparatus comprising the combination of a plurality of seriallyspaced die devices having opposed mating surfaces of sequentiallyvarying contours progressing from simple to more complex shape forsimultaneously pressing a strip of sheet metal therebetween at spacedintervals along the strip in formed increments having cross-sectionalshapes at each of said intervals in correspondence with the saidcontours of the respective die devices, the opposed mating surfaces ofeach of the die devices being spaced from the opposed mating surfaces ofnext adjacent die devices to free the strip from compressionintermediate of said spaced intervals, actuating means to simultaneouslyactuate all of said die devices in successive pressing operations topress a said increment of said strip by each of said die devices in eachpressing operation, the strip free of compression intermediate of theopposed mating surfaces of next adjacent die devices graduallyconforming lengthwise of the strip from the cross-sectional shapepressed at each interval to the crosssectional shape pressed at the nextsucceeding interval, and advancing means for simultaneously advancingthe strip sequentially through said die devices during the interimbetween said successive pressing operations in successive incrementscorresponding to the formed incremen ts pressed by the respective diedevices.

2. Apparatus as claimed in claim 1 and in which the opposed matingsurfaces of each die device are so disposed relative to the plane ofmovement of the die device that the component of force exerted by thesaid opposed mating surfaces in opposition to each other in saidpressing operations is maintained in said plane.

3. Apparatus as claimed in claim 1 and in which the opposed matingsurfaces of each die device are disposed normal to the plane of movementof the die device and disposed parallel to each other.

4. Apparatus as claimed in claim 1 and in which each die devicefollowing the first die device in said series of die devices has aforward face directed toward the preceding die device andan inwardlysloping wall extending from'said forward face toward the opposed matingsurfaces of the respective die device to provide a camming guide surfacefor said metal strip in being advanced to between the opposed matingsurfaces of the respective die device.

5. Apparatus comprising the combination of, a plurality of seriallyarranged die sets spaced at intervals along a course, said die sets eachhaving mating die surfaces of progressively varying contour from simpleto more complex form, operating means for successively operating all ofsaid die sets in unison to simultaneously press at all said intervals astrip of metal extending along said course through said die sets, themating die surfaces of the successive die sets progressively bendingsaid strip therebetween at said intervals into progressively variedcross-sectional forms corresponding to the said contours of the matingdie surfaces and in formed increments determined by the extentlengthwise of said course'of said mating die surfaces of the respectivedie sets, the mating die surfaces ofeach successive die set being spacedlengthwise of said course from the corresponding die surfaces of thepreceding die set a distance that is greater than the extent lengthwiseof said course of the mating die surfaces of said each successive dieset whereby the said strip may flex lengthwise of the course free ofcompression intermediate of said intervals during the bending of thestrip into said progressively varied cross-sectional forms by successivedie sets, and feed means synchronized With said operating means foradvancing said strip in successive increments between successivepressing operations of the die sets.

6. Apparatus as claimed in claim and in which the mating die surfaces ofeach of said die sets are so disposed in respect to each other and inrespect to the plane of relative movement between the mating diesurfaces as to maintain within said plane the components of forceproduced by pressing of said strip between said mating die surfaceswhereby thrust lengthwise of the course of one of the mating diesurfaces relative to the other is minimized.

7. Apparatus as claimed in claim 5 and in which the mating die surfacesof each die set are disposed lengthwise of said course at right anglesto the plane of relative movement between the mating die surfaces of therespective die sets.

8. Apparatus as claimed in claim 5 and in which each of thedie setssuccessively following the first die set of the series has a cammingguide surface directed toward the preceding die set for meeting thestrip as it is advanced by said feed means between successive pressingoperations and guiding the strip from the preceding die set to betweenthe mating die surfaces of the succeeding die set.

9. In combination, a plurality of sequentially arranged die devicespositioned at spaced intervals along a course for pressing between theopposed mating die surfaces of the die devices a strip of metalprogressing through the course into a series of cross-sectional formshaving progressively increasing bends, operating means forsimultaneously operating all said die devices to simultaneously presssaid strip at all of said intervals, said die devices being spaced aparta greater distance than the effective length of the mating die surfacesof the respective die devices to permit the strip to progressivelyconform lengthwise of the course without compression betweenthe diedevices to the cross-sectional form being pressed at a said die devicefrom the cross-sectional for-m being pressed at a preceding die device,and advancing means for advancing said strip in successiveincrementsalong the course during the interim between pressingoperations of said die devices to successively subject said incrementsto pressing by said sequentially arranged die devices.

10. The combination claimed in claim 9 and in which the die devicessequentially following the initial die device of the plurality of diedevices are provided with a sloping wall surface adapted to meet andguide the strip during its advancement between pressing operations fromthe preceding die device to between the opposed mating die surfaces ofthe following die device.

11. The method of producing a metal body of desired cross-sectional bentform from a sheet-metal strip, comprising the steps of simultaneouslypressing said strip at a plurality of spaced intervals in a series alongthe strip into a plurality of formed increments spaced apartlongitudinally of the strip and having cross-sectional bent formsprogressively varying in degrees of bent contour from simple form tosaid desired cross-sectional bent form; permitting said stripintermediate of said spaced intervals to flex free of compression duringsaid simultaneous pressing of the strip at said intervals to allow thestrip to progressively accommodate itself to the differences incross-sectional form at said intervals; releasing said strip from saidpressing operation; advancing said-strip while released an incrementcorresponding to said formed increment along said series of intervals;and consecutively repeating the described steps of pressing, permittingu to flex, releasing and advancing of said strip to progressivelyproduce the metal body of desired cross-sectional form from said strip.

12. The method as claimed in claim 11 and in which the metal strip whilereleased and being advanced a said increment is cammingly guided towarda succeeding interval in the cross-sectional bent form provided at apreceding interval from a location spaced from said preceding intervaland immediately preceding the next succeeding interval.

13. The method as claimed in claim 11 and in which the components offorce produced in said pressing of the strip are maintained in theplanes of the respective pressing movements to avoid working of themetal strip lengthwise of the strip by said pressing.

References (Iited in the file of this patent UNITED STATES PATENTS477,536 Guerber June 21, 1892 684,865 Richard Oct. 22, 1901 846,139Pruden Mar. 5, 1907 1,634,562 Shapiro July 5, 1927 1,708,872 Coates Apr.9, 1929 1,909,930 De Ridder May 23, 1933 2,295,131 Scott Sept. 8, 19422,405,738 Dettman Aug. 13, 1946 FOREIGN PATENTS 435,722 Great BritainSept. 26, 1935

